Optical device and optical module

ABSTRACT

The invention discloses an optical device and an optical module, the optical device includes a collimation lens arranged on an outer surface for converting incident light from a light source to parallel light, further includes a transmission light total reflection surface for totally reflecting a part of the parallel light at a first angle so that the part of the parallel light is finally coupled to an external optical fiber, a detection light total reflection surface for totally reflecting a part of the parallel light at a second angle so that the part of the parallel light is finally coupled to an external optical detector, and at least one attenuation light reflection surface for totally reflecting parallel light to be attenuated at a third angle before the parallel light leaves the optical device. The invention achieves the light intensity attenuation while realizing the direction-changing transmission of light signals.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. application Ser. No.14/197,160, filed on Mar. 4, 2014, which claims priority to ChinesePatent Application No. 201320162479.X, filed on Apr. 3, 2013, entitled“OPTICAL DEVICE AND OPTICAL MODULE”, which is hereby incorporated byreference in its entirety.

TECHNICAL FIELD

The present invention relates to the field of optical communicationtechnologies, in particular, to optical equipment, and moreparticularly, to an optical device with total reflection surfaces forachieving light signal transmission and light intensity attenuation, andan associated optical module.

BACKGROUND

In existing optical modules used in the field of optical communication,the transmission direction of a light beam emitted by a laser is changedto couple the light beam to an optical fiber, or the transmissiondirection of a received light beam in the optical fiber is changed tocouple the received light beam to a photoelectric detector. A pluralityof reflectors are usually obliquely arranged to change the transmissiondirection of the beams. A large number of reflectors are involved,complex structures are arranged, the assembly is complicated, and thenormal transmission of light signals is affected easily due to positionerrors. Therefore, it is proposed that an integrated optical device withmulti-structural-surfaces can be adopted to achieve thedirection-changing transmission of light signals. Generally, the lightemitted by the laser of the optical module is relatively large inintensity and needs to be attenuated before entering the optical fiber.Such optical device with multi-structural-surfaces usually includeslight-absorbing dielectric materials which are added to absorb light, soas to achieve the purpose of the light intensity attenuation. In thisway of attenuating the light intensity, not only the production processis complex, but also the degree of the light intensity attenuation isdifficult to control, thereby resulting in relatively low performance,relatively high cost and difficulty in producing of the optical device.

SUMMARY

One of the purposes of the invention is to provide an optical device, byarranging a plurality of total reflection surfaces in the opticaldevice, the purpose of light intensity attenuation is achieved while thedirection-changing transmission of light signals is realized, whichsolves the above technical problem in the prior art effectively.

In order to solve the above technical problem, the following technicalsolutions are provided in the present invention:

an optical device, including a collimation lens arranged on an outersurface and used for converting the incident light emitted by a lightsource to parallel light, the optical device further includes atransmission light total reflection surface used for totally reflectinga part of the parallel light transmitted by the collimation lens at afirst predetermined angle so that the part of the parallel light isfinally coupled to an external optical fiber, a detection light totalreflection surface used for totally reflecting a part of the parallellight transmitted by the collimation lens at a second predeterminedangle so that the part of the parallel light is finally coupled to anexternal optical detector, and at least one attenuation light totalreflection surface used for totally reflecting the parallel light to beattenuated which is transmitted by the collimation lens at a thirdpredetermined angle before the parallel light to be attenuated leavesthe optical device.

For the optical device as described above, there is one attenuationlight total reflection surface, the optical device further includes onetransmissive surface corresponding to the attenuation light totalreflection surface and used for transmitting all or part of thereflected light from the attenuation light total reflection surface.

For the optical device as described above, preferably, the attenuationlight total reflection surface is obliquely arranged at an inclinedangle of 45 degree with respect to the direction of the parallel lighttransmitted by the collimation lens, so as to achieve the directionchange of 90 degree of light signals. Moreover, the transmissive surfaceis preferably arranged vertical to the direction of the reflected lightfrom the attenuation light total reflection surface, so as to make allof the reflected light of the attenuation light total reflection surfacepass through the transmissive surface.

For the optical device as described above, there may be two attenuationlight total reflection surfaces, the optical device further includes twotransmissive surfaces corresponding, one to one, to the two attenuationlight total reflection surfaces and used for transmitting all or part ofthe reflected light from the corresponding attenuation light totalreflection surface.

Preferably, both the attenuation light total reflection surfaces areobliquely arranged at an inclined angle of 45 degree with respect to thedirection of the parallel light transmitted by the collimation lens, soas to achieve the direction change of 90 degree of light signals.Moreover, each of the two transmissive surfaces is preferably arrangedvertical to the direction of the reflected light from the correspondingattenuation light total reflection surface, so as to make all of thereflected light of the attenuation light total reflection surface passthrough the transmissive surface.

For the optical device as described above, in order to achieve thecoupling to the external optical fiber after the direction of the lightsignal is changed, a first focus lens is further arranged on an outersurface of the optical device and non-coplanar with the collimationlens, the transmission light total reflection surface is obliquelyarranged in a direction which forms an inclined angle of 45 degree withthe direction of the parallel light transmitted by the collimation lensso that the reflected light from the transmission light total reflectionsurface can be directly transmitted to the first focus lens.

For the optical device as described above, in order to facilitate themonitoring of the light signal intensity, the optical device furtherincludes a second focus lens arranged coplanar with the collimationlens, the optical device further includes one secondary total reflectionsurface, the detection light total reflection surface is obliquelyarranged in a direction which forms an inclined angle of 45 degree withthe direction of the parallel light transmitted by the collimation lensso that the reflected light from the detection light total reflectionsurface can be directly transmitted to the secondary total reflectionsurface, the secondary total reflection surface is obliquely arranged ina direction which forms an inclined angle of 45 degree with thedirection of the reflected light of the detection light total reflectionsurface so that the reflected light from the secondary total reflectionsurface can be directly transmitted to the second focus lens.

The invention also provides an optical module, the optical module adoptsan optical device of the above structure to achieve the transmission oflight signals.

Furthermore, an embodiment of the invention further provides an opticaldevice, which includes a light incident portion, and a light attenuationportion used for attenuating the light incident in the light incidentportion, the light attenuation portion includes an attenuation surface,the attenuation surface is an attenuation reflection surface or anattenuation transmissive surface.

The optical device as described above further includes a transmissionlight reflection portion used for changing the transmission direction ofthe incident light, the transmission light reflection portion includes atransmission light reflection surface, the transmission light reflectionsurface includes a coupling reflection surface and/or a detectionreflection surface; moreover, the transmission light reflection surfaceand the attenuation surface intersect, and at least some points ofintersection are located on the optical path of the incident light.

For the optical device as described above, the optical path of the lightprocessed by the attenuation surface and the optical path of the lightprocessed by the transmission light reflection surface do not intersect.

The transmission light reflection surface, the detection reflectionsurface and the attenuation surface intersect at one vertex, orthogonalprojection of the vertex in the plane where the light incident portionis located is in the light incident portion.

Compared with the prior art, the advantages and positive effects of theinvention are that: by arranging a plurality of total reflectionsurfaces in the optical device, the invention can achieve the purpose oflight intensity attenuation by utilizing the total reflection surfacesto allow a part of the light to be attenuated to leave the opticaldevice, while the direction-changing transmission of the light signal isrealized by utilizing the total reflection surfaces and the light signalis finally coupled to the output optical fiber for output, therebymultiple functions of the optical device is realized by using a simplestructure and reliable control, and the performance of use of theoptical device is improved.

After embodiments of the invention are read with reference to theaccompanying drawings, other characteristics and advantages of theinvention will become clearer.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic structural view of an embodiment of an opticaldevice according to the invention;

FIG. 2 is a schematic diagram of an optical path of an embodiment of anoptical module having the optical device of FIG. 1;

FIG. 3 is a schematic structural view of another embodiment of anoptical device according to the invention;

FIG. 4-FIG. 6 are schematic diagrams of optical paths of an embodimentof an optical module having the optical device of FIG. 3;

FIG. 7 is a partial structural view of an optical module having theoptical device of FIG. 3.

DESCRIPTION OF EMBODIMENTS

The technical solutions of the invention are further described in detailwith reference to the accompanying drawings and embodiments.

An embodiment of the invention provides an optical device, the opticaldevice includes a light incident portion, and a light attenuationportion for attenuating the light incident through the light incidentportion, the light attenuation portion includes an attenuation surface,the attenuation surface is an attenuation reflection surface or anattenuation transmissive surface.

Furthermore, the optical device may further include a transmission lightreflection portion for changing the transmission direction of theincident light, the transmission light reflection portion includes atransmission light reflection surface, the transmission light reflectionsurface includes a coupling reflection surface and/or a detectionreflection surface; moreover, the transmission light reflection surfaceand the attenuation surface intersect, and at least some of the pointsof intersection are located on the optical path of the incident light.

Where, the transmission light reflection surface and the attenuationsurface intersect, and some of the points of intersection are located onthe optical path of the incident light, which should be understood as:both the transmission light reflection surface and the attenuationsurface should be irradiated by the incident light; preferably, theorthogonal projection of the some of the points of intersection relativeto the plane on which the light incident portion is located is in thelight incident portion. On the other hand, the transmission lightreflection surface is configured to reflect the transmission light foruse, therefore, in another embodiment of the invention, all or part ofthe transmission light reflection surface can be modified to atransmission light transmissive surface, that is, the transmission lightmay pass through the transmission light transmissive surface for use.

It should be noted that, the optical path of the light processed by theattenuation surface and the optical path of the light processed by thetransmission light reflection surface do not intersect in the invention,so that the quality of the light processed by the transmission lightreflection surface is not affected.

The invention further provides an optical module, the optical moduleincludes a PCB and an optical device arranged on the PCB, the opticaldevice can adopt an optical device of the above-mentioned structure. Asan example, the optical device has a light incident portion, a lightattenuation portion and a transmission light reflection portion, forexample, the light incident portion is a lens, the light attenuationportion is at least one attenuation reflection surface and/or at leastone attenuation transmissive surface (the attenuation reflection surfacemay adopt, for example, a total reflection surface, the attenuationtransmissive surface may adopt, for example, a total transmissivesurface), the transmission light reflection portion is at least onereflection surface (e.g., a coupling reflection surface and/or adetection reflection surface). The following is one specific example ofthe optical device:

The optical device has a first lens, where the first lens (may be usedas the light incident portion) corresponds to a light-emitting component(e.g., a laser) arranged on the PCB and is used for receiving the lightemitted by the light-emitting component and converting the light toparallel light and then outputting the parallel light, the first lensmay be located right above the light-emitting component or at otherpositions, the first lens may be arranged on the outer surface of theoptical device or at other positions; the optical device also has atleast one attenuation reflection surface and/or at least one attenuationtransmissive surface (i.e., the light attenuation portion), the at leastone attenuation reflection surface receives the parallel light output bythe first lens and totally reflects a part of the parallel light andthen outputs the part of the parallel light, and/or the at least oneattenuation transmissive surface receives the parallel light output bythe first lens and enables a part of the parallel light to pass throughthe attenuation transmissive surface and then outputs the part of theparallel light. The interior of the optical device also has a couplingreflection surface and a detection reflection surface (the couplingreflection surface and the detection reflection surface constitute thetransmission light reflection portion), the coupling reflection surfaceis used for receiving the parallel light output by the first lens andtotally reflecting a part of the parallel light and then outputting thepart of the parallel light to a second lens, the second lens is locatedin the interior or on the surface of the optical device and is used forreceiving the light totally reflected by the coupling reflection surfaceand focusing the light and then outputting the light to the opticalfiber outside of the optical device for transmitting the light signal;the detection reflection surface and the coupling reflection surfacehave at least one vertex, the detection reflection surface is used forreceiving the parallel light output by the first lens and totallyreflecting a part of the parallel light and then outputting to amonitoring reflection surface, the monitoring reflection surface totallyreflects the incident light and then outputs to a light-receivingcomponent arranged on the PCB (e.g., an optical detector), thelight-receiving component detects the received light (e.g., lightintensity detection), thereby detecting the light intensity transmittedto the optical fiber.

When the light signal is transmitted, the light intensity transmitted tothe optical fiber needs to meet certain conditions upon the requirementsof applications, in the invention, the light attenuation portion is usedfor attenuating or consuming a part of the parallel light in the form ofreflecting them and/or making them passing through, thereby the part ofthe parallel light will not enter the optical fiber, so as to maintainthe light intensity coupled into the optical fiber.

In order to further improve the effect of the light attenuation portion,the light attenuation portion may be arranged as one or more totalreflection surfaces, and/or, one or more total transmissive surfacesaccording to the actual needs.

Further, the light attenuation portion may have at least one commonvertex with the coupling reflection surface and the detection reflectionsurface, the orthogonal projection of the at least one common vertexrelative to the plane where the first lens is located is in the firstlens, and/or at least some of the vertexes in these common vertexes arelocated on the optical path of the incident light from the lightincident portion. Preferably, the transmission light reflection surface,the detection reflection surface and the attenuation surface intersectat one vertex, which is similar to a vertex of a triangular pyramid, thetransmission light reflection surface, the detection reflection surfaceand the attenuation surface spread outwardly from this vertexrespectively, and the orthogonal projection of the vertex in the planewhere the light incident portion is located is in the light incidentportion.

In order to ensure the optical paths in the optical device not beingaffected by each other, the optical path of the light reflected by thecoupling reflection surface, the optical path of the light reflected byat least one attenuation reflection surface, the optical path of thelight transmitted by at least one attenuation transmissive surface, theoptical path of the light reflected by the detection reflection surface,and the optical path of the light reflected by the monitoring reflectionsurface do not intersect with each other.

The optical device described above may be integrally molded from thesame material, such as plastic; the inclined angle between the planewhere the coupling reflection surface/the attenuation reflectionsurface/the attenuation transmissive surface/the detection reflectionsurface/the monitoring reflection surface is located and the plane wherethe first lens is located can be set upon specific needs, as long as thelight incident thereon is totally reflected or totally pass through;moreover, if the material of the optical device is changed, the inclinedangle between the plane where the coupling reflection surface/theattenuation reflection surface/the attenuation transmissive surface/thedetection reflection surface/the monitoring reflection surface islocated and the plane where the first lens is located should be changedaccordingly, so that the light incident thereon is totally reflected ortotally pass through. In the following specific example, both theinclined angle between the coupling reflection surface and the planewhere the first lens is located and the inclined angle between thedetection reflection surface and the plane where the first lens islocated are 45 degree.

Preferably, the optical device described above is a solid structure, thelight transmission inside the optical device is actually the lighttransmission inside the medium of the material of the optical device.

Furthermore, in order to improve the light intensity received by thelight-receiving component arranged on the PCB, a third lens may be addedin the optical device, the third lens is located on the optical pathfrom the monitoring reflection surface to the light-receiving component,and may be arranged on the outer surface or in the interior of theoptical device and used for receiving the light reflected by themonitoring reflection surface and focusing the light and thentransmitting the light to the light-receiving component, so as tofurther improve the intensity of the light received by thelight-receiving component.

In one preferred embodiment, the light incident portion can adopt thecollimation lens 11 shown in FIG. 1, the light attenuation portion canadopt the attenuation light total reflection surface 161 shown in FIG. 1and/or the attenuation light total reflection surface 162 shown in FIG.3. Of course the attenuation light total reflection surface can also bereplaced with an attenuation light transmissive surface and/or anattenuation light semi-reflection semi-transmissive surface, to whichthe invention does not limit. Specifically, the coupling reflectionsurface can adopt the transmission light total reflection surface 14shown in FIG. 1, the detection reflection surface can adopt thedetection light total reflection surface 15 shown in FIG. 1, thetransmission light total reflection surface 14 and/or the detectionlight total reflection surface 15 constitutes the transmission lightreflection surface of the transmission light reflection portion.

Please refer to FIG. 1 and FIG. 2, where FIG. 1 is a schematicstructural view of an embodiment of an optical device according to theinvention, FIG. 2 is a schematic diagram of an optical path of anembodiment of an optical module having the optical device of FIG. 1.

As shown in FIG. 2, the optical module includes a PCB 2. A laser 3 usedas a light source and an optical detector 4 used for receiving a lightsignal, specifically for receiving the detection light signal, arearranged on the PCB 2. An example of the optical detector 4 is aphotoelectric detector, which monitors the light intensity transmittedto the coupling optical fiber through monitoring the light intensity ofthe detection light signal. Considering the overall size and the layoutof the internal structure of the optical module, the coupling opticalfiber 5 for transmitting the light signal with the outside is located onthe upper right of the laser 3, the light signal emitted by the laser 3cannot enter the coupling optical fiber 5 directly. In order to ensurethe smooth transmission of the light signal, the transmission directionof the light signal needs to be changed, so that the light signalemitted by the laser 3 is transmitted into the coupling optical fiber 5.Accordingly, the optical module of this embodiment is provided with anoptical device 1 which is arranged at a position above the PCB 2 andcorresponding to the laser 3 and the optical detector 4. The opticaldevice 1 is utilized for changing the transmission direction of thelight signal emitted by the laser 3, so as to couple the light signal tothe coupling optical fiber 5 smoothly to realize the transmission of thelight signal. The optical device 1 can also attenuate the intensity ofthe light signal while realizing the function of direction-changingtransmission of the light signal, so as to avoid the excessively stronglight signal which does not meet the requirement entering the couplingoptical fiber 5. Furthermore, in view of the overall structure of theoptical module, the optical device can also be utilized for detectingthe intensity of the light signal output from the coupling optical fiber5. In order to achieve the above functions, the optical device 1 mayhave the structure shown in FIG. 1.

Specifically, as shown in FIG. 1, combined with FIG. 2, the opticaldevice 1 of this embodiment has a first surface 191 facing the PCB 2 anda second surface 192 perpendicular to the first surface 191. Acollimation lens 11 and a second focus lens 13 are arranged on the firstsurface 191, and a first focus lens 12 is arranged on the second surface192. The collimation lens 11 corresponds to the laser 3 on the PCB 2,the second focus lens 13 corresponds to the optical detector 4, and thefirst focus lens 12 corresponds to the coupling optical fiber 5. Threetotal reflection surfaces are arranged above the collimation lens 11,including a transmission light total reflection surface 14, a detectionlight total reflection surface 15 and an attenuation light totalreflection surface 161. These three total reflection surfaces have acommon vertex, and extend and spread outwardly from the vertex.Moreover, the optical device 1 also has one secondary total reflectionsurface 18 corresponding to the detection light total reflection surface15 and the second focus lens 13, and one transmissive surface 171corresponding to the attenuation light total reflection surface 161. Andeach of the above-mentioned surfaces of the optical device 1 is arrangedaccording to the following requirements of the transmission direction ofthe optical path.

The transmission light total reflection surface 14 is obliquely arrangedat an inclined angle of 45 degree with respect to the parallel lighttransmitted by the collimation lens 11, and this arrangement enables thetransmission light total reflection surface 14 to receive a part of theparallel light from the collimation lens 11 which will be transmittedoutwardly through the coupling optical fiber 5, and the reflected lightwhich is reflected by the transmission light total reflection surface 14can be directly transmitted to the first focus lens 12.

The detection light total reflection surface 15 is obliquely arranged atan inclined angle of 45 degree with respect to the parallel lighttransmitted by the collimation lens 11, and this arrangement enables thedetection light total reflection surface 15 to receive a part of theparallel light from the collimation lens 11 which will be detected bythe optical detector 4, and the reflected light which is reflected bythe detection light total reflection surface 15 can be directlytransmitted to the secondary total reflection surface 18. And thesecondary total reflection surface 18 is obliquely arranged in thedirection which forms an inclined angle of 45 degree with the directionof the reflected light of the detection light total reflection surface15 so that the reflected light of the secondary total reflection surface18 is directly transmitted to the second focus lens 13.

The attenuation light total reflection surface 161 is obliquely arrangedat an inclined angle of 45 degree with respect to the parallel lighttransmitted by the collimation lens 11, and this arrangement enables theattenuation light total reflection surface 161 to receive a part of theparallel light to be attenuated from the collimation lens 11, and thereflected light which is reflected by the attenuation light totalreflection surface 161 is directly transmitted to the transmissivesurface 171 which is vertical to the direction of the reflected light.

The light transmitted outwardly through the coupling optical fiber 5,the light detected by the optical detector 4, and the light to beattenuated are pre-set according to the actual needs of the lighttransmission system. Thus, after the light intensity and positions ofthese lenses are determined, the positions of each total reflectionsurface and the transmissive surface in the optical device 1 can bedetermined upon the above requirements of the transmission direction ofthe optical path.

The optical device 1 having the above-described structure may be appliedto the optical module shown in FIG. 2, and the transmission direction ofthe optical path thereof and the process is as follows:

The scattered light with strong intensity emitted by the laser 3 isincident on the collimation lens 11, and then converted to parallellight by the collimation lens 11 to be output. A part of the parallellight output by the collimation lens 11, as transmission light actuallyoutput by the optical module, is incident on the transmission lighttotal reflection surface 14, and is then transmitted towards the rightside to the first focus lens 12 on the second surface 192 after beingtotally reflected by the transmission light total reflection surface 14,and then transmitted to the pre-set coupling optical fiber 5 after beingfocused and coupled by the first focus lens 12. A part of the parallellight output by the collimation lens 11, as the detection lightproportional to the transmission light actually output by the opticalmodule, is incident on the detection light total reflection surface 15.The detection light is transmitted towards the left side to thesecondary reflection surface 18 after being totally reflected by thedetection light total reflection surface 15, and then incident on thesecond focus lens 13 after its direction is changed by the secondaryreflection surface 18. The second focus lens 13 focuses the detectionlight and then the detection light is received by the optical detector4. By analyzing the intensity of the detection light received by theoptical detector 4, the intensity of the transmission light output bythe coupling optical fiber 5 can be obtained. The rest of the parallellight output by the collimation lens 11, as attenuation light to beattenuated, is incident on the attenuation light total reflectionsurface 161. The attenuation light is transmitted forward to thetransmissive surface 171 after being totally reflected by theattenuation light total reflection surface 161, and leaves the entireoptical device 1 after passing through the transmissive surface 171.Thereby the intensity of the light signal emitted by the laser 3 isattenuated.

By arranging the above total reflection surfaces and transmissivesurface on the optical device 1, the light intensity can be attenuatedby the total reflection surfaces and the transmissive surface, meanwhilethe direction-changing transmission of the light signal is realized bythe total reflection surfaces so that the light signal is finally outputoutwardly and the intensity of the output light signal is detected.Thus, not only the structure is simple and easy to achieve, but alsolight signals with different intensity can be attenuated by changingpositions of the total reflection surfaces, of which the control issimple and reliable.

In practical applications, the optical device 1 is not limited to theuse of one total reflection surface shown in FIG. 1 and FIG. 2 forattenuating the light intensity, but may also use two or more totalreflection surfaces.

FIG. 3 shows a schematic structural view of another embodiment of anoptical device according to the invention, and FIG. 4 shows a schematicdiagram of an optical path of an embodiment of an optical module havingthe optical device of FIG. 3.

As shown in FIG. 3 and FIG. 4, the optical module also includes a PCB 2.A laser 3 used as a light source and an optical detector 4 used forreceiving a light signal, specifically for receiving the detection lightsignal, are arranged on the PCB 2. Similar to the embodiment of FIG. 2,the coupling optical fiber 5 of the optical module of the embodiment ofFIG. 4 which is used for transmitting the light signal with the outsideis also located on the upper right of the laser 3. Similarly, an opticaldevice 1 is arranged at the position above the PCB 2 and correspondingto the laser 3 and the optical detector 4.

The optical device 1 has the structure shown in FIG. 3. Specifically,similar to the embodiment of FIG. 1, the optical device 1 of thisembodiment also has a first surface 191 facing the PCB 2 and a secondsurface 192 perpendicular to the first surface 191. A collimation lens11 and a second focus lens 13 are arranged on the first surface 191, anda first focus lens 12 is arranged on the second surface 192. Thecollimation lens 11 corresponds to the laser 3 on the PCB 2, the secondfocus lens 13 corresponds to the optical detector 4, and the first focuslens 12 corresponds to the coupling optical fiber 5. Different from theembodiment of FIG. 1, the optical device 1 of the embodiment of FIG. 3has four total reflection surfaces arranged above the collimation lens11, including a transmission light total reflection surface 14, adetection light total reflection surface 15, an attenuation light totalreflection surface 161 and an attenuation light total reflection surface162. These four total reflection surfaces have a common vertex, andextend and spread outwardly from the vertex. Moreover, the opticaldevice 1 also has one secondary total reflection surface 18corresponding to the detection light total reflection surface 15 and thesecond focus lens 13, one transmissive surface 171 corresponding to theattenuation light total reflection surface 161, and one transmissivesurface 172 corresponding to the attenuation light total reflectionsurface 162.

The arrangements and positions of the transmission light totalreflection surface 14, the detection light total reflection surface 15,the secondary total reflection surface 18, the attenuation light totalreflection surface 161 and the transmissive surface 171 are the same asthose of the embodiment of FIG. 1, for which please refer to thedescription of the embodiment of FIG. 1, which will not be repeatedhere. Only the arrangements and positions of the attenuation light totalreflection surface 162 and the corresponding transmissive surface 172are described here. The attenuation light total reflection surface 162and the attenuation light total reflection surface 161 are arrangedsymmetrically, and the transmissive surface 172 and the transmissivesurface 171 are arranged symmetrically, constituting a structure forattenuating the intensity of the light emitted by the laser 3.Specifically, the attenuation light total reflection surface 162 isobliquely arranged at an inclined angle of 45 degree with respect to theparallel light transmitted by the collimation lens 11, and thisarrangement enables the attenuation light total reflection surface 162to receive a part of the parallel light to be attenuated from thecollimation lens 11, and the reflected light which is reflected by theattenuation light total reflection surface 162 is directly transmittedto the transmissive surface 172 which is vertical to the direction ofthe reflected light.

It should be noted that, in the above-described embodiments, the lightreflected by the detection light total reflection surface and the lightreflected by the transmission light total reflection surface do notintersect, and the light reflected by the attenuation light totalreflection surface and the light reflected by the transmission lighttotal reflection surface do not intersect, so as to ensure the qualityof the light which is reflected by the transmission light totalreflection surface and finally coupled to the external optical fiber.

The optical device 1 having the structure of FIG. 3 may be applied tothe optical modules shown in FIG. 4, FIG. 5 and FIG. 6, and thetransmission direction of the optical path thereof and the process is asfollows:

The scattered light with strong intensity emitted by the laser 3 isincident on the collimation lens 11, and then converted to parallellight by the collimation lens 11 to be output. A part of the parallellight output by the collimation lens 11, as the transmission lightactually output by the optical module, is incident on the transmissionlight total reflection surface 14, and is then transmitted towards theright side to the first focus lens 12 on the second surface 192 afterbeing totally reflected by the transmission light total reflectionsurface 14, and then transmitted to the pre-set coupling optical fiber 5after being focused and coupled by the first focus lens 12. A part ofthe parallel light output by the collimation lens 11, as the detectionlight proportional to the transmission light actually output by theoptical module, is incident on the detection light total reflectionsurface 15. The detection light is transmitted towards the left side tothe secondary reflection surface 18 after being totally reflected by thedetection light total reflection surface 15, and then incident on thesecond focus lens 13 after its direction is changed by the secondaryreflection surface 18. The second focus lens 13 focuses the detectionlight and then the detection light is received by the optical detector4. By analyzing the intensity of the detection light received by theoptical detector 4, the intensity of the transmission light output bythe coupling optical fiber 5 can be obtained. The rest of the parallellight output by the collimation lens 11, as the attenuation light to beattenuated, is divided into two parts: one part is incident on theattenuation light total reflection surface 161 and is transmittedforward to the transmissive surface 171 after being totally reflected bythe attenuation light total reflection surface 161, and leaves theentire optical device 1 after passing through the transmissive surface171; the other part is incident on the attenuation light totalreflection surface 162 and is transmitted backward to the transmissivesurface 172 after being totally reflected by the attenuation light totalreflection surface 162, and leaves the entire optical device 1 afterpassing through the transmissive surface 172. Thereby the intensity ofthe light signal emitted by the laser 3 is attenuated, as shown in FIG.5. Furthermore, a total transmissive surface may also be used to realizethe intensity attenuation of the light signal, as shown in FIG. 6, wherethe parallel light incident on the total transmissive surface (notshown) totally pass through the total transmissive surface and leavesthe optical device.

Finally, it should be noted that, although the attenuation light totalreflection surface 161, the transmission light total reflection surface14 and the detection light total reflection surface 15 are arranged atan inclined angle of 45 degree with the parallel light transmitted bythe collimation lens 11 in the above two embodiments, which is anoptimal angle and easiest to implement, it is not limited to this angle.Other angles can also be used for the arrangement, as long as the totalreflection can be achieved and the subsequent transmission of theoptical path can be met. In addition, the transmissive surfaces 171 and172 are also not limited to being arranged perpendicular to thedirection of the reflected light of the corresponding attenuation lighttotal reflection surface, but may also be arranged in other angles, aslong as the light which meets the intensity requirement can pass throughthe transmissive surfaces. Moreover, the part of the parallel lightemitted by the collimation lens 11 is not limited to be directlytransmitted to the first focus lens 12 immediately after being reflectedby the transmission light total reflection surface 14 of only one stage,but may also be reflected by reflection surfaces of several stages afterbeing reflected by the transmission light total reflection surface 14and finally transmitted to the first focus lens 12. Correspondingly, thedetection light is also not limited to be reflected and focused by onlythe detection light total reflection surface 15, the secondary totalreflection surface 18 and the second focus lens 13, but may also betransmitted to the second focus lens 13 after reflections of morestages. And, the second focus lens 13 is also an optional structure, thesecond focus lens 13 may not be provided when the area of the opticaldetector 4 is large enough to directly receive the parallel light whichmeets the requirement.

The orthogonal projection of the common vertex of the transmission lighttotal reflection surface 14, the detection light total reflectionsurface 15, the attenuation light total reflection surface 161 and theattenuation light total reflection surface 162 in the above FIG. 1-FIG.4 relative to the plane where the collimation lens is located is in thecollimation lens, as shown in FIG. 7 which is a partial schematic viewof an optical module having the optical device of FIG. 3. Theabove-mentioned common vertex is shown in the upper portion of FIG. 7,and the collimation lens and the plane where the collimation lens islocated are shown in the lower portion of FIG. 7. In summary, theforegoing embodiments are only intended for describing the technicalsolutions of the invention other than limiting the invention; althoughthe invention has been described in detail with reference to exemplaryembodiments, those skilled in the art should understand that they maymake modifications to the technical solutions of the invention or makesubstitutions to some technical features thereof; these modifications orsubstitutions will not make the essence of the corresponding technicalsolutions depart from the spirit and scope of the technical solutionsclaimed by the invention.

What is claimed is:
 1. An optical device, comprising: a collimation lensarranged on an outer surface thereof for converting incident lightemitted by a light source to parallel light; a transmission light totalreflection surface for totally reflecting a part of the parallel lighttransmitted by the collimation lens at a first predetermined angle sothat the part of the parallel light is finally coupled to couplingoptical fiber; a detection light total reflection surface for totallyreflecting a part of the parallel light transmitted by the collimationlens at a second predetermined angle so that the part of the parallellight is finally coupled to an optical detector; and at least oneattenuation light transmission surface or at least one attenuation lightsemi-reflection semi-transmission surface, respectively for transmittingor for semi-reflecting semi-transmitting the parallel light to beattenuated which is transmitted by the collimation lens before theparallel light to be attenuated leaves the optical device; wherein thetransmission light total reflection surface, the detection light totalreflection surface and the attenuation light transmission surface meetat a common vertex, or the transmission light total reflection surface,the detection light total reflection surface and the attenuation lightsemi-reflection semi-transmission surface meet at a common vertex. 2.The optical device according to claim 1, wherein there is only one ofthe attenuation light transmission surface or only one of theattenuation light semi-reflection semi-transmission surface, and theoptical device further comprises one transmissive surface correspondingto the attenuation light transmission surface or the attenuation lightsemi-reflection semi-transmission surface and used for making all orpart of reflected light from the attenuation light transmission surfaceor the attenuation light semi-reflection semi-transmission surface passthrough the transmissive surface.
 3. The optical device according toclaim 2, wherein the attenuation light transmission surface or theattenuation light semi-reflection semi-transmission surface is obliquelyarranged at an inclined angle of 45 degree with respect to a directionof the parallel light transmitted by the collimation lens.
 4. Theoptical device according to claim 2, wherein the transmissive surface isarranged vertical to a direction of the reflected light from theattenuation light transmission surface or the attenuation lightsemi-reflection semi-transmission surface.
 5. The optical deviceaccording to claim 1, wherein there are two of the attenuation lighttransmission surfaces or there are two of the attenuation lightsemi-reflection semi-transmission surfaces, and the optical devicefurther comprises two transmissive surfaces corresponding, one to one,to the attenuation light transmission surfaces or the attenuation lightsemi-reflection semi-transmission surfaces and used for making all orpart of the reflected light from the corresponding attenuation lighttransmission surface or the attenuation light semi-reflectionsemi-transmission surface pass through the two transmissive surfaces. 6.The optical device according to claim 5, wherein both the attenuationlight transmission surfaces or both the attenuation lightsemi-reflection semi-transmission surfaces are obliquely arranged at aninclined angle of 45 degree with respect to a direction of the parallellight transmitted by the collimation lens.
 7. The optical deviceaccording to claim 5, wherein each of the two transmissive surfaces isarranged vertical to a direction of the reflected light from thecorresponding attenuation light transmission surface or thecorresponding attenuation light semi-reflection semi-transmissionsurface.
 8. The optical device according to claim 1, wherein a firstfocus lens is further arranged on an outer surface of the optical deviceand non-coplanar with the collimation lens, and the transmission lighttotal reflection surface is obliquely arranged in a direction whichforms an inclined angle of 45 degree with the direction of the parallellight transmitted by the collimation lens so that reflected light fromthe transmission light total reflection surface can be directlytransmitted to the first focus lens.
 9. The optical device according toclaim 8, wherein the optical device further comprises a second focuslens arranged coplanar with the collimation lens and one secondary totalreflection surface, the detection light total reflection surface isobliquely arranged in a direction which forms an inclined angle of 45degree with the direction of the parallel light transmitted by thecollimation lens so that reflected light from the detection light totalreflection surface can be directly transmitted to the secondary totalreflection surface, and the secondary total reflection surface isobliquely arranged in a direction which forms an inclined angle of 45degree with the direction of the reflected light of the detection lighttotal reflection surface so that reflected light from the secondarytotal reflection surface can be directly transmitted to the second focuslens.
 10. An optical module, comprising: a PCB and the light source, theoptical detector, the coupling optical fiber, and the optical deviceaccording to claim 1, wherein the light source and the optical detectorare arranged on the PCB.
 11. The optical module according to claim 10,wherein there is only one of the attenuation light transmission surfaceor there is only one of the attenuation light semi-reflectionsemi-transmission surface in the optical device, and the optical devicefurther comprises one transmissive surface corresponding to theattenuation light transmission surface or the attenuation lightsemi-reflection semi-transmission surface and used for making all orpart of reflected light from the attenuation light transmission surfaceor the attenuation light semi-reflection semi-transmission surface passthrough the transmissive surface.
 12. The optical module according toclaim 11, wherein the attenuation light transmission surface or theattenuation light semi-reflection semi-transmission surface is obliquelyarranged at an inclined angle of 45 degree with respect to a directionof the parallel light transmitted by the collimation lens; or thetransmissive surface is arranged vertical to a direction of thereflected light from the attenuation light transmission surface or theattenuation light semi-reflection semi-transmission surface.
 13. Theoptical module according to claim 10, wherein there are two of theattenuation light transmission surfaces or there are two of theattenuation light semi-reflection semi-transmission surfaces in theoptical device, and the optical device further comprises twotransmissive surfaces corresponding, one to one, to the two attenuationlight transmission surfaces or the two attenuation light semi-reflectionsemi-transmission surfaces and used for making all or part of thereflected light from the corresponding attenuation light transmissionsurface or the corresponding attenuation light semi-reflectionsemi-transmission surface pass through the two transmissive surfaces;wherein both the attenuation light transmission surfaces or both theattenuation light semi-reflection semi-transmission surfaces areobliquely arranged at an inclined angle of 45 degree with respect to adirection of the parallel light transmitted by the collimation lens, oreach of the two transmissive surfaces is arranged vertical to adirection of the reflected light from the corresponding attenuationlight transmission surface or the corresponding attenuation lightsemi-reflection semi-transmission surface.
 14. The optical moduleaccording to claim 10, wherein a first focus lens is further arranged onan outer surface of the optical device and non-coplanar with thecollimation lens, and the transmission light total reflection surface isobliquely arranged in a direction which forms an inclined angle of 45degree with the direction of the parallel light transmitted by thecollimation lens so that reflected light from the transmission lighttotal reflection surface can be directly transmitted to the first focuslens.
 15. The optical module according to claim 14, wherein the opticaldevice further comprises a second focus lens arranged coplanar with thecollimation lens and one secondary total reflection surface, thedetection light total reflection surface is obliquely arranged in adirection which forms an inclined angle of 45 degree with the directionof the parallel light transmitted by the collimation lens so thatreflected light from the detection light total reflection surface can bedirectly transmitted to the secondary total reflection surface, and thesecondary total reflection surface is obliquely arranged in a directionwhich forms an inclined angle of 45 degree with the direction of thereflected light of the detection light total reflection surface so thatreflected light from the secondary total reflection surface can bedirectly transmitted to the second focus lens.
 16. An optical device,comprising: a light incident portion; and a light attenuation portionfor attenuating a part of incident light passing the light incidentportion, wherein the light attenuation portion comprises an attenuationsurface, and the attenuation surface is an attenuation reflectionsurface; the light attenuation portion comprises an attenuation lighttransmission surface or an attenuation light semi-reflectionsemi-transmission surface, respectively for transmitting or forsemi-reflecting semi-transmitting parallel light to leave the opticaldevice; and a transmission light reflection portion for changing atransmission direction of a part of incident light passing the lightincident portion, the transmission light reflection portion comprises atransmission light reflection surface, the transmission light reflectionsurface comprises a coupling reflection surface and/or a detectionreflection surface; and, the transmission light reflection surface andthe attenuation surface intersect, and at least some intersection pointsare located on an optical path of the incident light; the transmissionlight reflection portion comprises a detection light total reflectionsurface for totally reflecting parallel light.
 17. The optical deviceaccording to claim 16, wherein an optical path of light processed by theattenuation surface and an optical path of light processed by thetransmission light reflection surface do not intersect.
 18. The opticaldevice according to claim 16, wherein the transmission light reflectionsurface, the detection reflection surface and the attenuation surfaceintersect at one vertex, orthogonal projection of the vertex in a planewhere the light incident portion is located is in the light incidentportion.